We plan to continue our investigations on aspects of the origin and metabolic fate of taurine. The characterization of hypotaurine animotransferase will be pursued. The purification and characterization of this enzyme in mammalian tissue contrasting it to the parallel omega amino acid transaminase (GABA transaminase) will be carried forth. The biosynthesis and metabolism of the new amino acid of mammalian cystine metabolism, cysteine thiosulfonate, will be investigated. The development of a new gas chematography procedure to determine taurine in tissues will be advanced.